Also, it is my understanding that there were improvements to the 3.2L Intermediate Shaft (IMS), that also may be significant to the longevity of the engine. I am not an expert on this, but the update occurred sometime in the 2005MY. There have been volumes written about it, nothing really conclusive, but it may influence some to favor a later 3.2L or any 3.4L 987S.
vincesf